We wanted to address some of the questions raised by commenters. So here’s a summary of the more common themes:

What do the anesthesiologists think of the research?

Not much. Here’s the official reaction from the American Society of Anesthesiologists. Billing data is a poor way to judge quality and outcomes, and can’t distinguish between complications stemming from a surgical procedure and from anesthesia, ASA president Alexander Hannenberg tells the Health Blog. He says the study didn’t include enough cases to capture any significant differences in mortality rates, given that mortality is exceedingly rare — one estimate is one death per 240,000 anesthetics. He also cites an ASA-funded survey that found that the public wants physicians to supervise their anesthesia.

What are the requirements for CRNAs?

We wrote: “Prerequisites for becoming a CRNA include a bachelor of science degree in nursing or science-related field, one year of critical care experience before a two- or three-year master’s program in anesthesia, a certification exam and a year of residency.” But an AANA spokesperson referred us to this page listing the education and experience necessary to becoming a CRNA. The year of residency we mentioned is not on it, and so we will correct the original post.

Since the AANA sponsored the study, shouldn’t we dismiss its conclusions?

As with many fields, much of the research in this area is funded by folks with skin in the game. One 2000 study published in Anesthesiology concluded that mortality rate and so-called “failure to rescue,” or mortality rate after complications, “were lower when anesthesiologists directed care.” (That study actually also involved billing data.) It was funded mostly by independent sources but “the development of the methodology” was partially funded by a grant from the American Board of Anesthesiology (which is separate from the ASA).

So what kind of study would settle this question?

One that isn’t likely to be done. To satisfy everyone, it would have to be large enough to capture any statistically significant differences in mortality rates, be based on clinical rather than billing data and be independently funded. The CDC considered doing a study in 1980, Hannenberg says, but concluded that “mortality rates were so low that it was near impossible.” And mortality rates are lower now, which would make the project even harder.

How can CRNAs be found more cost effective than anesthesiologists?

We asked Paul Hogan, an economist and vice president with the Lewin Group (an independent consulting unit of UnitedHealth) and an author of a recent cost-effectiveness study of anesthesia delivery (and yes, it was funded by AANA). That study ran simulations of different delivery models and concluded that in most (but not all) cases, CRNAs acting independently provide anesthesia services at the lowest economic cost.

This will hinge on demand, the characteristics of the anesthesia procedures and the mix of payers — Medicare doesn’t make a distinction, but private payers will, on average, reimburse (or “allow” in insurance-speak) at lower rates for care delivered by a solo CRNA than by other provider mixes. If CRNAs were allowed to provide more services, eventually, Hogan says, “you’d expect the price for those services to go down.” (In addition, more physicians, including anesthesiologists, are being employed directly by hospitals and surgical centers, in some cases guaranteeing a certain salary.)

Here’s what the ASA had to say about Hogan’s study, in case you were wondering.

Correction: A previous version of this post incorrectly stated that the ASA funded the 2000 Anesthesiology study.

Comments (5 of 62)

I just had my surgery cancelled. I was assured that an anesthesiologist would be performing my anesthesia; 5 minutes before the surgery I'm told that a CRNA would be doing my case...she told me that she was equivilent to any anesthesiologist..fortunately, my wife was present in the holding area and told the CRNA off..."I respect your 20 month's fo nurse anestetise training but you are NOT an anesthesiologist and you are UNSAFE to work without supervision" My wife asked the CRNA several anesthesia emergency questions and the CNA totally folded. My wife pf 30+ years is supportive of qualified midlevals (CRNA), but not if the try to practice "solo"... CRNA arent qualified to practice without anesthesiologist supervision...stanley and others here are correct; nurses (CRNA) may have the legal authoity to provide nurse anesthesia solo, but it's unsafe..use common snese.......my wife is a physician....yep, now that this is known I have an anesthesiologist doing my entire case with no CRNA

9:31 am November 26, 2011

solo crna are dangerous wrote :

Anesthesia is the prctice of medicine not nursing. Nurses (CRNA) should not be allowed to practice without anesthesiologist supervision. Period. Consider: the education and training of an anesthesiologist vs a CRNA-no comparison to a ohysician's education and a nurses 20 month or so CRNA program). Do anesthesiologist's have to "rescue" CRNA? Sure, all the time. What happens when that anesthesiologist isn't there? I would never allow a CRNA to participate in any of my cases without anesthesiologist management.

12:44 pm August 23, 2011

patient x wrote :

I recently had the misfortune of having an unsupervised crna do my fairly simple anesthetic; it was a disaster and she didn't have the foggiest idea as to how to manage a simple complication. heck, I almost died from this experience....you DO NOT want a CRNA doing your case unless closely supervised...and maybe the CRNA should stick to nursing..I'm a board-certifer MD

11:00 pm October 14, 2010

cycler wrote :

dear anonymous. Which ever anonymous you are. after posting that last comment I noticed that you (anonymous) have multiple postings that are toxic to say the least. Best anesthesia provider period. Who are you kidding? Your big accomplishments are medical school and TEE. Wow, jump back! Be proud o your abilities, not pompous. Do your best to ensure everyone is doing their best anesthesia. You may just learn more.

10:43 pm October 14, 2010

cycler wrote :

dear Anonymous, I think that identifier says it all. Are you really a thoracic surgeon? My guess is you are a disgruntled anesthesiologist, quite possibly one who has lost his contract. Once again, it is not an argument of playing doctor, the argument is about providing excellent anesthesia. Doctors and nurses have respective educational programs to produce board certified anesthesia providers. Both must prove sufficient knowledge and skill to perform anesthesia. Both produce excellent anesthetists. Unfortunately, both also produce incompetent, thoughtless, and careless anesthetists. I have been in practice for 26 years and I have seen many good and bad decisions made by both MDs and CRNAs. There is a bell shape curve for every specialty. We would like everyone to be on the far right, but that will never happen, someone always slips through the cracks. Regarding the bell shape curve, there is only one for anesthesia. There is not one for MDs and one for CRNAs. We are all on the same curve. I choose to remain on the far right by keeping my knowledge and skills as up to date and sharp as possible. I also continue to do my best in educating my colleagues in anesthesia, both CRNA and MD.